Objectives: To evaluate the usefulness of clinical parameters in screening for early SpA in patients meeting Calin's criteria for inflammatory back pain (IBP).
Methods: General practitioners used Calin's criteria for IBP to refer patients younger than 45 years to our early SpA clinic. We obtained the patients' medical history and performed a clinical examination including plain X-rays and magnetic resonance images of all affected areas. Laboratory tests for acute-phase reactants and HLA-B27 were also obtained. Two rheumatologists made a diagnosis of SpA according to the existing criteria.
Results: Of the 92 patients referred, 30 (33%) were diagnosed with SpA and 62 (67%) with a non-inflammatory disorder. Spontaneous awakening night pain, the presence of Calin's criteria for IBP and tenderness of the SI joints (SIJs) were independently associated with SpA. Neck pain and reduced cervical spine sagittal movement occurred mostly with non-inflammatory disease. A history of night pain and improvement of pain with exercise but not with rest, as well as expression of HLA-B27 and abnormal CRP levels were significantly more common in patients with SpA.
Conclusions: Specific clinical symptoms such as spontaneous awakening night pain, cervical pain and tenderness of the SIJs on clinical examination appear useful in screening younger patients with back pain for early SpA.